A minimum of 100 million doses of Covishield - a coronavirus vaccine that this morning was said to be 90 per cent effective under certain conditions - will be available by January and hundreds of million could be ready by the end of February, Adar Poonawalla of the Serum Institute of India told NDTV on Monday evening. A single dose (two are recommended at this stage) will cost up to ₹ 1,000 if purchased from the pharmacy, but the government will buy 90 per cent of the supply at ₹ 250 per dose, he explained.